Throttle issues while on highway

The basic forum. Want to show off your XJ or ask questions about it? Maybe you're not sure where to post? Put it here.
Post Reply
User avatar
BCooper
Lookin' Around
Lookin' Around
Posts: 50
Joined: Thu Sep 06, 2012 10:13 am

Recently while riding I've run into situations while riding on the highway at high speeds. I've asked about this before and it turns out its not vapor lock or the fuel filter because I've replaced both and the issue still persists. What happens is after about 20 miles or so at about 80 mph (i-10 west :)) the throttle become erratic. Shortly after my speed slows to about 55 mph even if i'm full on the throttle. I'm positive it's a fuel issue because after I stop and give the bike time to catch up in idle it will return to normal. However sometimes if i let off the gears and press the clutch the bike will shut off. If I'm travelling 200 miles or so I repeat this at least 10-12 times while riding on the highway. I've noticed the rate of improvement correlates with how long i let the bike sit which is why the vapor lock would make sense. But I've opened left the gas cap open while this is happening and it has absolutely no effect :wallbash: .

Theres is one thing that I have in question which is my aftermarket vacuum pump. I decided to ditch the oem pump because they make no buils for them and to purchase brand new its about $130! I currently use a Mikuni df-44 which is popular among snowmobiles and similar 600cc motors. I've been informed buy many that it was a good replacement and they make repair kits for $25 :Mozarkrider: .
Image

Would the pump have any effect on the sluggish behavior? I've replaced all of the hoses within the past 3 months so i find it hard to believe theres a leak somewhere especially because visually I see nothing wrong. I do however notice air bubbles in the fuel pump hose but im not sure. Maybe I'm missing a hose i dont know but i need help.

Another thing is when im travelling uphill it happens much quicker. Also this problem stopped after a while but its started up bother times i've changed my oil not to say it means anything it could be a coincidence. Let me know your thoughts and thanks for the input in advance.
"Live, love, bless, adventure and don't be sorry" - JK

This topic has 5 replies

You must be a registered member and logged in to view the replies in this topic.


Register Login
 
Post Reply